Those approved by Access Center MUST take the exam at Access Center
Covered topics:
1. Reading List in class webpage: Chapters and sections covered
2. LAB Assignments: must review your LAB work!!!
LAB1pre: Variables in C, stack usage;
LAB1 : myprintf function, partitiion table
LAB2pre: C sructures, Link list processing, binary tree
PROC structure
ksleep()/kwakeup()
kfork(), kexit(), kwait()
LAB2 : mysh program: fork-execve-exit-wait; I/O redirection, PIPE
LAB3pre: threads, mutex lock
LAB3: Gauss Elimination by threads
FILE operations: mkdir, chdir, getcwd
stat and ls program
cat, cp programs
system call vs Library I/O functions
========================== SAMPLEs =========================================
LAB1pre Part1: C variables in a.out file: READ Chapter 2.3.1, 2.3.2
Given a C program with GLOBAL variable, LOCAL variables, which variables are
in a.out file?________________ WHY?_______________________________________
Stack contents: READ Chapter 2.4.1, 2.4.2, 2.4.3
Given main(int argc, char *argv[]){ int a=1,b=2; A(a,b); }
int A(int x, int y){ int u, v; HERE: }
Draw a diagram of stack contents from HERE: to argv of main()
Identify the STACK FRAME of A() function.
myprintf(char *fmt, . . .)
{ char *cp; int *ip; ....}
Given printu(u32 x),
Write code for printd(int x) ______________________
Write code to let cp point at the fmt string_______________________
Write code to let ip point at the first item to be printed on stack__________
Partition table:
How did you get MBR of a virtual disk into char buf[512]?
Write code to print the TYPE of partition 3 in MBR:
What's an extended partition?
Chapter 2.10: Link List Processing
Write C statements to define a node structure containing:
name : array of 64 chars
key : int
next : pointer to next node;
Given a link list of NODEs as defined above,
Write C code to print the names of the list elements.
Write code to INSERT a new node to the END of a list
Write code to delete a node with a given key value
LAB2pre:
What's a process? ______________________
What does ksleep() do?___________________
What does kwakeup() do?__________________
How does a process terminate? ___________
What does pid=wait(int *status) do?____________
Processes form a BINARY tree by child, sibling pointers.
Assume: PROC *p kfork() a child *q.
(1). Write code to insert q into CHILD list of p: _______________
(2). write code to print child list of p: ________________________
LAB#2: sh simulator <========== EXTREMELY IMPORTANT!!!!
READ Chapter 3.8.1: fork()
Chapter 3.8.3: Process termination
Chpater 3.8.4: pid = wait(int *status)
Chapter 3.8.6: execve()
Chapter 3.9 : I/O redirection
Chapter 3.10.2: Pipe command processing
For any Linux command, how does Linux sh find the command?__________________
Write code to tokenize PATH into dir[0], dir[1],..._________________________
ASSUME:
YOUR sh gets a command line = "cmd one two three"
Wrtie C code to tokenize line into char *myargv[ ].
Write C code to execute cmd, passing as parameters myargv and env
YOUR main sh's logic:
while(1){
get a command line;
tokenize the command line;
for non-trivial command:
fork a child (EXACT code): ______________________________________
if (parent){ wait for child to die: EXACT code:_________________
repeat while loop: EXACT code: ____________________
}
else{
// CHILD sh do the command line
}
}
----------------------------------------------------------------
CHILD sh: for a command line = CMD a b c d > outfile
Write code to do > outfile: ___________________________________________
MAY be < :
Create a pathname = dir[i]/cmd: CODE: ________________________________
Create myargv[ ]: Show myargv[ ] EXACTLY: ___________________________
int r = execve(pathname, myargv, env);
What if the execve() call succeeds? ________________________________
What if the execve() call fails? ___________________________________
Assume command line = cat filename | grep printf
Write C code to do the pipe _____________________________________________
==========================================================================
Chapter 4: Concepts on Concurrent Programming
Threads vs. Process: What are threads?
How to create threads? _______________________
What does thread_join() do? _______________________
What's the difference between thread_barrier() and thread_join()?
What's a Critical Region? _______________________
How to protect Critical Regions __________________
In Gauss elimination: What's partial pivoting? ________________________
Why partial pivoting? ________________________
Given linear equstions A.X = B
What's LU decomposition? _______________________________________________
After converting A = L.U, how to solve for X? _________________________
==========================================================================
Chapter 7: File Operation Levels:
Fle operation commands: mkdir, rmdir, cd, pwd, chmod
Write down syscall function for each: ______ _____ _____ _____ _______
Chapter 8: System calls: stat and ls program:
u16 st_mode:
How to tell a file is REGular ? ______________________________
DIRectory? ______________________________
LNKfile ? ______________________________
u32 st_ctime = 12345678:
what does the value mean? ________________________________________
How to convert st_ctime into CALENDAR form?_______________________
Write C code to print all the file names under Current Directory:
====================================================================
Chapter 9: Lib I/O Functions vs System calls.
Write C code to open filename for READ: _________________
then read 10 bytes: _________________
fopen filename for READ: _________________
then read 10 bytes: _________________
Relation between fopen and open? ____________________________
fread and read? ____________________________
When to use syscall? when to use Lib I/O functions?